JP3520867B2 - Signal processing device and its cooling method, and radio receiver provided with the signal processing device and its cooling method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal processing apparatus applied to a base station radio apparatus for mobile communication, satellite communication, etc., for cooling a high frequency receiving section to receive a desired signal, and a cooling method thereof.

[0002]

2. Description of the Related Art FIG. 2 is a block diagram showing the basic configuration of a conventional radio receiver. Hereinafter, description will be given with reference to this drawing.

A conventional radio receiver has an antenna terminal 1 and
A reception band-pass filter 2 for selecting a signal in a desired band from a reception signal input from the antenna terminal 1, and a reception low-noise amplifier 3 for amplifying the output of the reception band-pass filter 2 to a desired level with low noise. , And a reception signal output terminal 4 for outputting the reception signal amplified by the reception low noise amplifier 3. The reception band-pass filter 2 and the reception low-noise amplifier 3 are vacuum-sealed in a vacuum container 5, vacuum-insulated to the outside by a vacuum heat insulating layer 6, and cooled on a cooling stage 8 by a refrigerator 7. To be done. Further, a first power supply terminal 9 for supplying operating power to the reception low noise amplifier 3 and a second power supply terminal 10 for supplying operating power to the refrigerator 7 are provided respectively. The vacuum container 5 and the refrigerator 7 are housed in a housing 11.

The vacuum vessel 5 holds the inside in a vacuum state,
Vacuum heat insulation is performed by the vacuum heat insulating layer 6, so that the heat intrusion from the outside is blocked. The reception band pass filter 2 and the reception low noise amplifier 3 enclosed in the vacuum container 5 are cooled by the refrigerator 7 to an extremely low temperature of, for example, about 70K. Here, the refrigerator 7 can stably maintain an extremely low temperature of about 70 K for a long time by using a heat exchange cycle by compression / expansion of helium gas or the like, and a commercially available product should be used. You can

As described above, by cooling the reception band-pass filter 2 and the reception low noise amplifier 3 to an extremely low temperature, it is possible to reduce the thermal noise generated therein. As a result, the noise figure of the radio receiver shown in FIG. 2 is greatly improved, and the reception sensitivity is greatly improved. Therefore, by using the radio receiver shown in FIG. 2, it is possible to obtain a reception output of, for example, a prescribed C / N (carrier power / noise power) even for a received signal of a low level. C
It is possible to obtain the effect that the transmission power on the transmission side required to obtain the reception output of / N is small. The radio receiver is often installed outdoors or near the top of the antenna tower in order to reduce the loss until the received signal is input to the antenna terminal 1.

The inside of the vacuum container 5 must be maintained in a vacuum state for vacuum heat insulation. However, when the wireless receiver is installed outdoors or near the tower top of the antenna tower as described above for use as a base station for mobile communication, for example, it is necessary to be small and lightweight in order to facilitate the construction. . Therefore, it is not desirable to add a vacuum pump for constantly evacuating the inside of the vacuum container 5 to the wireless receiver. In addition, it is not desirable to externally use a vacuum pump that requires regular maintenance, because the maintenance interval is shortened and the operating cost for providing communication service is increased.

Therefore, as a means for keeping the inside of the vacuum container 5 in a vacuum state, it is general to provide a getter material 12 in the vacuum container 5 for suppressing an increase in gas pressure in the vacuum heat insulating layer 6. As the getter material 12, a material that can adsorb hydrogen gas is often used. The reason is that, in general, since the vacuum container 5 is made of a surface-treated stainless material, a large amount of hydrogen gas is contained as a gas discharged into the vacuum heat insulating layer 6. Also, the getter material 12
Is heat-treated in vacuum at a temperature determined according to its material. This exposes a clean and activated alloy surface capable of adsorbing a large amount of gas, so that gas adsorption can be started. Therefore, the getter material 12 has a heater 13 for activation incorporated therein and also has heater terminals 14 and 15 for energization. As such a getter material, for example, Zr (zirconium)
HS404 and HS405 made of alloys containing
Commercially available getter materials such as (trade name of Nippon Getters Co., Ltd.) can be used. Instead of such an alloy containing Zr as a main component, Ba (barium), Ti (titanium),
Alternatively, an alloy containing V (vanadium) as a main component may be used as the getter material.

Further, even if the getter material 12 is saturated with the adsorbed gas on the surface for adsorbing the gas, the getter material 12 can continue to adsorb the gas by performing the heat activation treatment again. The heat activation treatment is for not only releasing a part of the gas adsorbed on the surface of the getter material 12 into a vacuum but also incorporating a part of the gas into the getter material 12 from the surface layer. Therefore, the gas can be further adsorbed on the surface by the amount of the gas taken into the getter material 12.

In addition to this, it is also common to cool the inside of the vacuum container 5 to an extremely low temperature of, for example, about 70K. That is, the gas adsorbent 16 such as activated carbon is attached to the cooling stage 8, and it is operated as a mechanism that suppresses an increase in the gas pressure in the vacuum heat insulating layer 6 by utilizing the pseudo-gathering and trapping action of the gas that is remarkable at low temperature. With these measures, if the refrigerator 7 is continuously operated while keeping the low temperature,
It is known that the gas pressure in the vacuum heat insulating layer 6 can be kept low within a range where there is no problem for a long period of about 0 years.

[0010]

The getter material 12 is activated before the vacuum heat insulating layer 6 is vacuum-sealed. After that, the refrigerator 7 is not operated for a long period of two months or more and stored at room temperature, so that the gas pressure inside the vacuum heat insulating layer 6 may increase. In addition, the gas trapped by the gas adsorbent 16 may be released into the vacuum heat insulating layer 6 due to the refrigerator 7 stopping and the temperature rising due to a power failure or the like. However, in these cases, since the heat insulation from the outside is large due to the deterioration of the vacuum heat insulation, it may not be possible to cool even if the refrigerator 7 is started.

The present invention has been made in view of the above-mentioned circumstances, and when the cooling mechanism is stopped and the vacuum heat insulation is deteriorated so that the cooling mechanism cannot be cooled even if the cooling mechanism is started as it is, a vacuum is automatically generated. An object of the present invention is to provide a cooling method that enables cooling by a cooling mechanism by improving heat insulation, and a signal processing device having a mechanism that realizes the cooling method.

[0012]

In order to solve the above problems, the invention according to claim 1 is covered with a vacuum heat insulating layer, cooled by a cooling mechanism, and a signal processing unit for processing an input signal; A signal processing device equipped with a heat-activated getter material that suppresses an increase in gas pressure in the heat insulation layer and a heater that heats and activates the getter material. It is characterized by further including a control unit.

The invention according to claim 2 is a signal processing unit which is covered with a vacuum heat insulating layer, is cooled by a cooling mechanism, and processes an input signal, and heat which suppresses an increase in gas pressure in the vacuum heat insulating layer. An activation type getter material, and a signal processing device provided with a heater for heating and activating the getter material,
It is characterized by further comprising an energization control unit that energizes the heater at the start of cooling and switches energization to the cooling mechanism after a predetermined condition is satisfied.

The invention according to claim 3 relates to the signal processing device according to claim 2, characterized in that a certain time has elapsed after the satisfaction of the predetermined condition.

The invention according to claim 4 relates to the signal processing device according to claim 2 or 3, wherein the energization control section switches a power supply to either the cooling mechanism or the heater, and the relay. It is characterized by consisting of a sequencer for controlling the.

The invention according to claim 5 relates to the signal processing device according to any one of claims 1 to 4, characterized in that the main part of the signal processing part is made of a superconducting material. I am trying.

Further, the invention according to claim 6 relates to the signal processing device according to claim 5, characterized in that the superconducting material is a high-temperature superconductor.

The invention according to claim 7 is a radio receiver comprising the signal processing device according to any one of claims 1 to 6.

Further, the invention according to claim 8 is a signal processing section which is covered with a vacuum heat insulating layer, is cooled by a cooling mechanism and processes an input signal, and heat which suppresses an increase in gas pressure in the vacuum heat insulating layer. The present invention relates to a cooling method of a signal processing device including an activation type getter material and a heater that heats and activates the getter material, and is characterized by energizing the heater at the start of cooling.

The invention according to claim 9 is characterized in that it is covered with a vacuum heat insulating layer and cooled by a cooling mechanism to process an input signal, and heat for suppressing an increase in gas pressure in the vacuum heat insulating layer. The present invention relates to a cooling method of a signal processing device including an activation type getter material and a heater that heats and activates the getter material, energizing the heater at the start of cooling and energizing the cooling mechanism after a predetermined condition is satisfied. It is characterized by switching.

The invention according to claim 10 is the same as that of claim 9.
The method for cooling a signal processing device as described above is characterized in that a certain period of time has elapsed after the predetermined condition is satisfied.

The invention according to claim 11 is the invention according to claim 9.
Alternatively, according to the method of cooling the signal processing device of Item 10, it is characterized in that energization switching from the heater to the cooling mechanism is automatically realized by using a preset condition or a sequence program.

Further, the invention according to claim 12 is the invention according to claim 8.
The method for cooling a signal processing device according to any one of 1 to 11 is characterized in that a main portion of the signal processing unit is made of a superconducting material.

The invention according to claim 13 is the same as claim 1.
The method for cooling a signal processing device according to 2, wherein the superconducting material is a high temperature superconductor.

Further, the invention according to claim 14 is the invention according to claim 8.
A method for cooling a wireless receiver, including the method for cooling a signal processing device according to any one of items 1 to 13.

With the above configuration, the signal processing unit is cooled by the cooling mechanism, so that the thermal noise is significantly reduced. Further, since the signal processing unit is covered with the vacuum heat insulating layer, it is difficult for heat to enter. Therefore, the cooling mechanism can efficiently cool the signal processing unit, so that the power consumption can be suppressed low. Here, when the cooling mechanism is started after the cooling mechanism is stopped due to a power failure, or when the cooling mechanism is started after being vacuum-sealed and stored at room temperature for a long time, the gas pressure in the vacuum heat insulating layer increases. Therefore, the vacuum insulation has deteriorated considerably. Therefore, since the amount of heat inflow is too large as it is, the temperature of the signal processing unit is not sufficiently lowered even if the cooling mechanism is started. Therefore, in the present invention, when the cooling mechanism is started, the gas pressure in the vacuum heat insulating layer is lowered by previously heating and activating the getter material. This improves vacuum insulation and allows cooling by a cooling mechanism. Further, since the energization of the heater and the energization at the time of starting the cooling mechanism do not overlap with each other, the electric power supplied to the wireless receiver can be small in capacity.

Further, the main part of the wiring of the signal processing section may be made of a superconducting material, and the cooling mechanism may have the ability to cool the signal processing section until the superconducting material becomes superconducting. The superconducting material is, for example, a treble superconductor. As described above, by configuring the signal processing unit with a superconducting material that is in a superconducting state at a temperature cooled by the cooling mechanism, low loss characteristics of passing signals and sharp cut characteristics of frequency characteristics can be obtained. Further, when the superconducting material is particularly a high-tone superconductor, the temperature at which it is in a superconducting state is relatively high, so that a small, lightweight, and inexpensive cooling mechanism can be used.

Further, since the wireless receiver of the present invention is provided with a mechanism for detecting the activation of the cooling mechanism by starting the energization of the cooling mechanism, the cooling mechanism is automatically activated upon the restoration of the power supply, especially in the case of a power failure, The failure time of the wireless receiver can be shortened.

[0029]

Embodiments of the signal processing apparatus according to the present invention will be described below with reference to the drawings.
The description will be made in detail using examples. FIG. 1 is a block diagram showing the configuration of a radio receiver which is an embodiment of the signal processing device of the present invention. As shown in FIG. 1, the radio receiver of this example includes an antenna terminal 1, a reception band pass filter 2 for selecting a signal in a desired band from a reception signal input from the antenna terminal 1, and a reception band pass filter. Reception low noise amplifier 3 for amplifying the output of the device 2 to a desired level with low noise
And a reception signal output terminal 4 for outputting the reception signal amplified by the reception low noise amplifier 3. The reception band-pass filter 2 and the reception low-noise amplifier 3 are vacuum-sealed in a vacuum container 5, vacuum-insulated from the outside by a vacuum heat insulating layer 6, and cooled on a cooling stage 8 by a refrigerator 7. . Further, a first power supply terminal 9 for supplying operating power to the reception low noise amplifier 3 is provided.

Further, the refrigerator 7, the heating heater 13 prepared for activating the getter material 12, and the second power supply terminal 10 for supplying electric power to them are respectively provided in the relay 1
It is connected via 7. Relay 17 is sequencer 1
Controlled by 8. The vacuum container 5 and the refrigerator 7 are the housing 1
It is housed in 1. The sequencer 18 uses the second power supply terminal 10
It is supplied with power from the power source to operate, and is reset to the initial state each time it is activated, that is, each time when new power is supplied, and the programmed sequence is repeated.

That is, when energization is started, the sequencer 1
8 returns to the initial state, and first operates the relay 17 to energize the heater 13 for a predetermined time. This time, the heater 13
It is set in advance to a time necessary and sufficient for activating the getter material 12 by heating from. At this time, since power is supplied to the second power supply terminal 10 at a specified voltage of, for example, 48 V DC, the resistance value of the heater 13 is also made accordingly. At this time, the refrigerator 7 has not started yet, and therefore does not consume the limited amount of power supply. Therefore, the amount of power supplied can be suppressed. When the getter material 12 is activated, the gas in the vacuum heat insulating layer 6 is adsorbed, so that the vacuum heat insulation is improved.

Next, the sequencer 18 operates the relay 17 to supply electric power to the refrigerator 7. As a result, the refrigerator 7 starts up and starts cooling the cooling stage 8. At this time, since the state of vacuum heat insulation is improved, it becomes possible to cool within the refrigerating capacity of the refrigerator 7, and further, by cooling the cooling stage 8, the activated carbon 16 attached to the cooling stage 8 is removed. Further, the gas in the vacuum heat insulation layer 6 is adsorbed, the vacuum heat insulation is improved, and the cooling stage 8 is further cooled. Therefore, the sequencer 18 has a mechanism for detecting the start-up of the refrigerator 7 by starting energization of the refrigerator 7.

Therefore, especially in the event of a power failure, the refrigerator 7 is automatically started when the power is restored, and the failure time of the radio receiver can be kept short. Therefore, when the refrigerator 7 is started after being stopped at a room temperature for a long period of two months or more after the refrigerator 7 is stopped due to a power outage or after vacuum sealing,
If the refrigerator cannot be cooled even if the refrigerator 7 is started up due to deterioration of the vacuum insulation as it is, the vacuum insulation is automatically improved and the cooling mechanism start-up method that enables cooling by the refrigerator 7 and the start-up method are realized. It is possible to provide a wireless receiver characterized by having a mechanism for

The reception bandpass filter 2 may be made of a superconducting material which is in a superconducting state at a temperature cooled by the refrigerator 7. In this case, the reception band pass filter 2
Is formed of, for example, a microstrip line (not shown), and the ground layer and the signal line forming the microstrip line are both formed of a superconducting material. By forming the reception bandpass filter 2 from a superconducting material, the loss of the reception bandpass filter 2 can be significantly reduced,
The noise figure of the receiver can be greatly reduced. As a result, the sensitivity of the wireless receiver can be significantly improved.

A high temperature superconductor may be used as the superconducting material forming the receiving band pass filter 2. Examples of high-temperature superconductors include Bi-based, Tl-based, Hg-based, and Y-based
There are copper oxide superconductors such as those based on the system and Ag, and any of these can be used. Some high-temperature superconductors have a temperature at which the transition to the superconducting state exceeds 100K.
In such a superconductor, a superconducting state can be obtained by simply cooling the liquid nitrogen to a boiling point of about 77.4K under 1 atm. Therefore, the cooling capacity of the refrigerator 7 can be relaxed, and the cryogenic refrigerator 7 that is smaller and cheaper can be used. As a result, the wireless receiver can be made compact and inexpensive.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and it is apparent that the embodiments can be appropriately modified within the scope of the technical idea of the present invention. For example, in the above-described embodiment, the condition after the predetermined condition is satisfied is after a certain period of time has passed, but the present invention is not limited to this and may be after the constant pressure is reached.

Further, in the above-mentioned embodiments, the case of the radio receiver as the signal processing device to be used after cooling has been described, but the present invention is not limited to this, and can be applied to a signal processing device cooled by a refrigerator. . For example, a refrigerator-cooled infrared receiver or a SQUID (superconducting quantum)
interference device; superconducting quantum interference device), etc.
It goes without saying that it can be applied to other refrigerator-cooled devices.

[0038]

As described above, according to the configuration of the present invention, the heater is energized at the start of cooling, or the heater is energized at the start of cooling and then the cooling mechanism is energized after a predetermined condition is satisfied. Even if the cooling mechanism is started after the cooling mechanism has stopped due to, for example, or if the cooling mechanism is started after being stored at room temperature for a long time after vacuum sealing, the gas pressure in the vacuum heat insulating layer at the start of starting the cooling mechanism is controlled. Since it can be lowered, cooling by the cooling mechanism becomes possible.

Further, by using a superconducting material for the wiring of the signal processing section, low loss of passing signals and sharp cut characteristics of frequency characteristics can be obtained, and a small, lightweight and inexpensive cooling mechanism can be used. it can.

In other words, according to the configuration of the present invention, the signal processing unit includes the signal filter and / or the signal amplifier, and the signal processing unit is covered with the vacuum heat insulating layer.
It is a wireless receiver that cools with a cooling mechanism, and a heat-activated getter material with a built-in heater for activation is installed in the vacuum heat insulation layer as a mechanism to suppress an increase in gas pressure in the vacuum heat insulation layer. In the wireless receiver described above, when the cooling mechanism is activated, the heater for heating is energized to heat and activate the getter material, and a method for activating the cooling mechanism and a mechanism for automatically realizing the activation method are provided. . by this,
After the refrigerator stops due to a power failure or after it is stored at room temperature for a long time after vacuum sealing, the gas pressure in the vacuum heat insulation layer is increased by the action of the heat-activated getter material when the refrigerator is started. The state of vacuum insulation can be improved. Therefore, cooling by the refrigerator is possible.

Further, according to the structure of the present invention, a radio having a signal processing unit including a signal filter and / or a signal amplifier, and covering the signal processing unit with a vacuum heat insulating layer and cooling with a cooling mechanism. In a receiver, a wireless receiver in which a heat-activated getter material containing a heating heater for activation is installed in the vacuum heat insulating layer as a mechanism for suppressing an increase in gas pressure in the vacuum heat insulating layer, When the cooling mechanism is started, the heating heater is energized in advance, the getter material is heated and activated, and then the cooling mechanism is started, and the starting method is automatically realized. By having a mechanism to operate, after the refrigerator is stopped due to a power outage or after it is stored at room temperature for a long time after vacuum sealing, the function of the heat-activated getter material is effective when the refrigerator is started. Reducing the gas pressure in the heat insulating layer, it is possible to improve the state of the vacuum thermal insulation. Therefore, cooling by the refrigerator is possible. Further, since the energization of the heater and the energization at the time of starting the cooling mechanism do not overlap with each other, the electric power supplied to the wireless receiver can be small in capacity.

As described above, according to the present invention, the vacuum heat insulation is automatically improved when the vacuum heat insulation deteriorates due to the stop of the cooling mechanism and cannot be cooled even if the cooling mechanism is started as it is. It is possible to provide a method of activating a cooling mechanism that enables cooling by means of a radio receiver and a radio receiver characterized by having a mechanism that automatically realizes the method of activation.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a conventional wireless receiver.

FIG. 2 is a block diagram showing a configuration of a wireless receiver that is an embodiment of the present invention.

[Explanation of symbols]

1 antenna terminal 2 Reception band pass filter (Signal processing unit) 3 Reception low noise amplifier (Signal processing unit) 4 Received signal output terminal 5 vacuum container 6 Vacuum insulation layer 7 Refrigerator (cooling mechanism) 8 cooling stages 9 First power supply terminal 10 Second power supply terminal 11 housing 12 getter material 13 Heating heater 14, 15 Heater terminals 16 Activated carbon (gas adsorbent) 17 Relay (energization controller) 18 Sequencer (energization controller)

Continuation of front page (56) Reference JP 2000-246922 (JP, A) JP 2001-144635 (JP, A) JP 2001-136083 (JP, A) JP 11-186922 (JP, A) JP-A-10-224269 (JP, A) JP-A-10-135525 (JP, A) JP-A-10-126290 (JP, A) JP-B-52-26401 (JP, B2) (58) Fields investigated (Int.Cl. ⁷ , DB name) F24F 11/02 102 H04B 1/00

Claims (14)

(57) [Claims] 1. A signal processing unit which is covered with a vacuum heat insulating layer, is cooled by a cooling mechanism, and processes an input signal, and a heat activation type getter material which suppresses an increase in gas pressure in the vacuum heat insulating layer. A signal processing device comprising a heater that heats and activates the getter material, further comprising an energization control unit that energizes the heater when cooling is started. 2. A signal processing unit which is covered with a vacuum heat insulating layer, is cooled by a cooling mechanism, and processes an input signal, and a heat activation type getter material which suppresses an increase in gas pressure in the vacuum heat insulating layer. A signal processing device including a heater that heats and activates the getter material, further comprising an energization control unit that energizes the heater at the start of cooling and switches energization to the cooling mechanism after a predetermined condition is satisfied. A signal processing device characterized by the above. 3. The signal processing device according to claim 2, wherein the condition after the predetermined condition is satisfied is after a predetermined time has elapsed. 4. The energization control unit includes a relay that switches energization to either one of the cooling mechanism and the heater,
4. The signal processing device according to claim 2, comprising a sequencer for controlling this relay. 5. The signal processing device according to claim 1, wherein a main portion of the signal processing unit is made of a superconducting material. 6. The signal processing apparatus according to claim 5, wherein the superconducting material is a high temperature superconductor. 7. A radio receiver comprising the signal processing device according to claim 1. 8. A signal processing unit which is covered with a vacuum heat insulating layer, is cooled by a cooling mechanism, and processes an input signal, and a heat-activated getter material for suppressing an increase in gas pressure in the vacuum heat insulating layer. A cooling method for a signal processing device comprising a heater for heating and activating the getter material, wherein the heater is energized at the start of cooling. 9. A signal processing unit which is covered with a vacuum heat insulating layer and is cooled by a cooling mechanism to process an input signal, and a heat activation type getter material which suppresses an increase in gas pressure in the vacuum heat insulating layer. A method of cooling a signal processing device, comprising a heater for heating and activating the getter material, characterized in that the heater is energized at the start of cooling and the energization is switched to the cooling mechanism after a predetermined condition is satisfied. A method for cooling a signal processing device. 10. The method for cooling a signal processing device according to claim 9, wherein the predetermined condition is satisfied after a predetermined time has elapsed. 11. The method of cooling a signal processing device according to claim 9, wherein switching of energization from the heater to the cooling mechanism is automatically realized by using a preset condition or a sequence program. 12. The method for cooling a signal processing device according to claim 8, wherein a main portion of the signal processing unit is made of a superconducting material. 13. The method for cooling a signal processing device according to claim 12, wherein the superconducting material is a high temperature superconductor. 14. A method for cooling a wireless receiver, including the method for cooling a signal processing device according to claim 8.